This invention relates generally to an adapter which can be used on a rod and more particularly, but not by way of limitation, to an adapter which enables a rod used in a well to be rotated by tubing tongs. The invention also relates to a method of rotating a rod relative to a string of one or more rods used in a well.
In testing and completing an oil well, for example, it is well known that a tubing string can be used in such jobs as logging, perforating and flowing the well. A tubing string comprises individual tubular members which are connected together at joints in end-to-end manner. Each joint is typically a threaded coupling wherein one end of one tubular member is screwed in an end of another tubular member. The screwing, or rotating, action by which one tubular member is connected to or disconnected from another tubular member is imparted by means of tubing tongs, a known type of equipment which is commonly found at a site where a well is being drilled or completed or which is otherwise readily available in the oil and gas industry.
In producing an oil well, for example, it is well known that a string of rods, sometimes referred to as sucker rods, is sometimes needed to pump oil up from a subterranean formation intersected by the well. The rods are connected end-to-end at joints which typically include threaded coupling collars. Typically, adjacent ends of adjacent rods have the same configurations which include threaded pin ends. These ends are screwed into opposite ends of a coupling collar to form the joint between the two adjacent rods. Thus, as with the aforementioned tubular members, to connect or disconnect one rod to or from another rod, one of the rods needs to be rotated relative to the other.
Because rods have smaller diameters than tubular members, however, this rotating could not heretofore be accomplished with the prevalent tubing tongs. Instead, apparatus known as rod tongs have been required to connect and disconnect rods; however, rod tongs have not been as prevalent as tubing tongs so that when one needs to connect or disconnect rods, there may be a delay in obtaining the relatively scarce rod tongs and it may also be more expensive to use rod tongs instead of tubing tongs (for example, because of additional costs or lost revenues brought about by a delay in obtaining the rod tongs and because of higher fees which may be charged to provide the relatively scarce rod tongs).
In view of the prevalence of tubing tongs compared to rod tongs, it would be desirable, to overcome the deficiencies noted above, to be able to use tubing tongs to rotate rods in assembling or disassembling rod strings used in a well. Thus, there is the need for an apparatus and method which would permit this.